According to the fairy tale there was an old man, and an old woman, and a little boy. One morning the old woman made a Johnny-cake, and put it in the oven to bake. The old man and the old woman went out and began to hoe potatoes, and left the little boy to tend the oven. But he didn’t watch it all the time, and all of a sudden he heard a noise, and he looked up and the oven door popped open, and out of the oven jumped Johnny-cake, and went rolling along end over end, towards the open door of the house. He passes through many adventures. On went Johnny-cake, and by-and-by he came to a bear and wolf and escaped from them. But then he met the fox. Who could deceive him and ate him.

From here the phrase “Johnny-cake” comes, which is used to describe a fat person.